1 divided by 7 plus one seventh multiplied by 99 2013 multiplied by 2011 2012 If you want to calculate the above two questions, you need to simplify them,

1 divided by 7 plus one seventh multiplied by 99 2013 multiplied by 2011 2012 If you want to calculate the above two questions, you need to simplify them,

1 original formula = 1 △ 7 + 1 / 7 * 99
=1/7+99/7
=(99+1)/7
=100/ 7
2 original formula = 2013 × (2011 / 2012)
=2013×(1-1/2012)
=2013-2013/2012
=2011 and 2011 / 2012
If you have any other questions, please take this question and ask for help,

The label of the fan-shaped statistical chart is "the fan-shaped statistical chart of the number of left behind children in the whole school", which specifically refers to the number of people, that is, 20% refers to the number of people. It is impossible to complete all the problems of this question according to 20% of 6 people and 4 × 6 = 24 people, What can be understood as 20% of the class number of 6 left behind children can complete this problem. Is there any problem in question 23 of Chongqing's 2011 senior high school entrance examination? The label of the fan-shaped statistical chart is: "fan-shaped statistical chart of the number of left behind children in the whole school", which specifically refers to the number of students

(1) If the class with 6 left behind children accounts for 20% of the whole school class, then there are 4 left behind children in each class on average; (2) if the class with 6 left behind children accounts for 20% of the whole school left behind children, then there are 120 left behind children in the school, then there are 22 left behind children in the class with 2 left behind children

Xiaohong's family had a balance of 500 yuan last year and 950 yuan this year. Their income is 15% higher than that of last year and their expenditure is 10% lower than that of last year. How much is their income and expenditure this year?

The income and expenditure of xiaohongjia this year are respectively X and Y yuan
Then: X-Y = 950
X*(1-0.15)-Y*(1-0.1)=500……………………
The results are as follows
X=17100
Y=16150

In the plane rectangular coordinate system, it is known that a (- 1.0) B (0.2) point C is in the second quadrant, CD ⊥ X axis, perpendicular foot is D, and △ CDA ≌ △ AOB, e is the moving point on the BC extension line. Through a.b.e, make a circle O ', connect AE, and there is another point F on the circle O', and AF = AE, AF intersects BC at point G, connect BF
(1) Verify af * BG = Ag * BF
(2) If the parabola y = ax ^ 2 + AX-2 passes through the point C, the analytic expression of the parabola can be obtained
(3) Is there two points P and Q on the parabola of (2) such that the quadrilateral abpq is a square? Find the coordinates of P and Q; two points
(3) no need to do the second question. I'm sure I can do the third question, and I don't have a picture to take with me

You'd better ask the teacher about the questions you don't understand, and get the answers on the Internet

1. It is known that the parabola y is equal to the square of half x plus x plus C, and there is no intersection point with X axis
(1) Find the value range of C
(2) Determine the quadrant of the line y + CX + 1
2. The price of a certain brand bottled beverage is 26 yuan per case. A store promotes the bottled beverage by "buy one get three free". If you buy the whole case, you will get three free bottles per case, which is equivalent to 0.6 yuan cheaper than the original price. How many bottles are there in a case of this brand beverage?

One
1) C is greater than 0 [the larger the parabola is on the y-axis, the farther it is from the x-axis
2) 123 quadrant [y + CX why? Is y = right!
two
10 bottles
26|x+3|5=26\x+3

Want n mathematical equation problems want equation problems don't want problems
Equations, no problems
One dollar a time
Urgent!

1. 2(x-2)-3(4x-1)=9(1-x)
2. 11x+64-2x=100-9x
3. 15-(8-5x)=7x+(4-3x)
4. 3(x-7)-2[9-4(2-x)]=22
5. 3/2[2/3(1/4x-1)-2]-x=2
6. 2(x-2)+2=x+1
7. 0.4(x-0.2)+1.5=0.7x-0.38
8. 30x-10(10-x)=100
9. 4(x+2)=5(x-2)
10. 120-4(x+5)=25
1\ 50x+10=60
2\ 60x-30=20
3\ 3^20x+50=110
4\ 2x=5x-3
5\ 90=10+x
6\ 90+20x=30
7\ 691+3x=700
8\105=100-x
9\65=21x-44

No equations
For a project, it takes 8 days for Party A to do it alone and 10 days for Party B to do it alone. After several days of cooperation between the two teams, team a has another task to transfer, and team B has another 7 days to complete the rest of the project. How many days have the two teams cooperated?

(1-7 / 10) / (1 / 8 + 1 / 10) = 3 / 10 / 9 / 40 = 4 / 3 days

Please write a formula instead of an equation
1. There is a cuboid fish tank 80 cm long, 60 cm wide and 30 cm high, which contains some water, and a piece of ornamental stone sinks in the water. If the ornamental stone is fished out, the water surface will drop by 2 cm. What is the volume of the ornamental stone?

The volume of the ornamental stone is the same as that of the rising water
Volume of ornamental stone: 80 × 60 × 2 = 9600cm

x+60/x+x-60=2/3

x+60/x+x-60=2/3
x+60/2x-60=2/3
x+60=2(2x+60)/3
x+60=4x+120/3
3(x+60)=4x+120
3x+180=4x+120
4x-3x=180-120
x=60

Arrange 0.123, 0.213, 0.312, 0.132, 0.321, 0.32, 0.23, 0.31, 0.13, 0.21, 0.12, 0.1, 0.2 and 0.3 from small to large
————————————————————————————————————————————
Add a 0.231

0.1